Sound reproducer



Aug. 13, 1929. F. MILLER 1,724,611

SOUND EPRoDUcER Filed Aug. 1'7, 1927 2 Sheets-Sheet l Fm. l g 'L "llulllllf l Illlllmllll t b 5 i- .E 5 1| l 61 *44' 65 l l l l 60 \/45 69/ m ez 48 'lo l 4o 42.' /\/A 45 4 E i 4\ @En r Fna. z '[11] 46 44 lllllunlnmuw l 70 42 M /ifr W 47 l? F75. 5 y

mvramow` FRANK musa RTTORNEYS Patented Aug. 13, 1929.

UNITED STATES PATENT OFFICE.

FRANK MILLER, OF LOS A1\TG{ELESCALIFORNIA,v ASSIGNOR OF ONE-HALF TO TONY ANTHONY BARBER, OF LOS ANGELES, CALIFORNIA.

SOUND REPROD'UCER.

Application filed August 17,

My invention is a sound reproducer of the phonograph type reproducing sound by the vibratlon of a needle due to the action of a disc with sound recorded thereon.

My invention has several objects such as improvements in the amplifier horn and in a sound am lier mounted internally of the horn.

The amplifying horn is constructed of wood and is made substantially pyramidal in shape withthe apex adjacent the connection to the tone arm. In the horn I mount a sound amplifierwhich has a relatively small tube extending lengthwise of the horn, and a bell end on the tube which is covered by a perforated cap. Surrounding this cap I have a disc of wood, and outside of the wood there is a cover plate. On the tube connected to two bridges I have a number of copper wires strung which are under tension, thereby forming vibrating wires.

The effect of the amplifier in the horn is that it appears to form a resonance chamber, and is constructed of a material which readily takes up vibration, and this, with the disc made preferably of gum wood, gives a vibrating element in the horn which greatly amplifies the so und. The wires strung tightly under1 tension on the tube of the amplifier appear to set up vibrations and to affect the amplifying of the sound.

y invention is illustrated in the accompanying drawings, in which:

Figure l is a longitudinal section of my sound reproducer taken substantially on the line l-l of Figure 3 in the direction of the arrows.

Figure 2 is a vertical transverse section taken on the line 2 2 of Figure l or Figure 4 in the direction of the arrows, looking into the horn and at the face of the amplifier'.

Figure 3 is a horizontal section taken substantially on the line 3 3 of Figure l or 4 in the direction of the arrows.

Figure 4 is a vertical longitudinal section taken on the line 4-4 of Figure 2 in the direction of the arrows.

Figure 5 is a vertical transverse section of Figure 4 showing in detail the horn and amplifier.

The horn is constructed substantially as follows, having reference particularly to Figures l through 5. The horn has a back sup- 1927. Serial N0. 213,514.

porting strut 40 which is supported on the floor 41 of the cabinet. There is a lower board 42 which extends from the support 40 to the front 43 of the cabinet. The upper board 44 extends from the front of the cabinet from the back 45, and there are two vertical side boards 46. The meeting edges 47 of these various boards converge towards the inner end 48, this being substantially the apex of a pyramid with steep sides, the base of the pyramid being reached by the open front of the cabinet. This horn has an opening 50 adjacentv its inner end for receiving the lower part 50 of the tone arm. The horn is preferably constructed of wood of the character to give a. free and good vibration.

My sound amplified built into the horn is constructed substantially as follows, this being illustrated particularly in Figures l through 5. The amplifier is designated generally by the numeral and comprises a small tube 56 having an open inner end 57. This tube enlarges into a bell 58 which has a flange 59. A cover 60 is welded at the end of the bell inside of the flange and has an internal and depressed central section 6l. There are a series of perforations 62 through this cover 60. A disc 63 formed of wood (preferably gum wood) is secured to the flange 59 by small screws or the like. This disc is illustrated in Figure 2 and is preferably hexagonal on its periphery. The cover plate 65 is secured by countersunk screws 66 to the wood disc 63, there being metal sleeves 67 sourrounding the screws. This cover plate has a series of perforations 68 and an outwardly curved central section 69. The wooden disc is centered in the horn by means of lower and upper centering screws 70 and 71.

The inner end of the tube 56 has a bridge 72 in the form of a flat ring which engages the sides of the pyramidalshaped horn. There is another bridge 73 secured 'to the bell 58 by soldering or the like, this bridge also being in the form of a flat ring. These bridges are connected .by a series of tightly drawn wires 74.

In constructing the sound amplifier, I preferably construct a tube 56 of copper and also the bell of copper. The cover 60 is preferably formed of brass. The disc 63 is from the spirit thereof, as set forth in thel description, drawings and claims.

I claim :l l

l. In a sound reproducer, a horn having a sound amplifier built therein, said amplifier having a small tubular end at the inner part of the horn and a belled part towards the outer end of the horn, a pair of ringlike bridges secured to the small end of the horn andto the bell, and tightly stretched wires between the said bridges.

2. In a sound reproducer, a horn having a sound amplier built therein, said amplifier having a small inner end substantially cylindrical enlarging into a bell, the bell having a perforated outwardly curved cover, bridges secured to the inner end ofthe ring and to the bell, and tightly drawn wires connecting the said bridges.

3. In a sound reproducer, as claimed in claim 2, the cover of the bell having a depressed central section pressed inwardly, the

perforations vsurrounding the inwardly pressed section.

4. In a sound reproducer having a horn formed of wood and of pyramidal internal shape with the apex connected to a tone arm, a sound amplier'built inthe horn comprising a small tubular end substantially cylindrical adjacent the apex of the horn, a belled enlargement of the tube having a perforated outwardly curved cover secured to the end of the bell, a ringV of Wood secured to the cover, anda perforated cover plate secured to the ring of wood and spaced therefrom, said cover plate being spaced also from the cover of the bell.

5. In a sound reproducer, a horn having a sound amplifier built therein, said amplifier having a small tube at thepinner end, a bell forming an extension of said tube, an outwardly curved cover with perforations secured to the bell, a perforated cover plate secured in front of the cover, the cover of the bell having a ring of Wood secured there.- to, and the cover plate being attached to the wood ring and spaced therefrom.

In testimony whereof I have signed my name to this specification.

FRANK MILLER. 

